Biology: Cell Theory

Cell Theory states..

All living things are made of cells, cells are the unit of function of living things, and all cells come from existing cells.

Nucleus

An organelle that is the cell’s control centre, it is considered the 'brain of the cell.

Cytoplasm

An organelle that is a thick, gel-like substance that suspends the organelles.

Cell Membranes

An organelle that controls the movements of substances in and out of the cell.

Cell wall

An organelle that supports and strengthens the cell, found only in plants.

Chloroplast

An organelle that captures light for photosynthesis, found only in plants.

Difference between Animal and Plant Cells

In plants, chloroplasts, the cell wall, and one vacuole are found; a central nucleus and multiple vacuoles are found in animal cells.

Levels of organisation

Cells - Tissue - Organs - Systems - Organisms

How are new cells produced?

Cells are produced through cell division, also known as mitosis.

Mitosis

The process by which new cells are created so that multicellular organisms can grow, repair and reproduce

Eukaryote

Cells that contain structures surrounded by membranes. e.g. plants, animals, fungi

Prokaryote

Cells that don't have structures surrounded by membranes. e.g. bacteria.

Unicellular

Organisms that consist of a single cell. e.g. yeast, bacteria

Multicellular

Organisms that are made of many cells. e.g. animals, plants, some fungi

specialised cells

Cells that have special shapes and features to assist with their function.

How is cell structure related to its function?

A cell structure helps it to perform specialised tasks